Huge landslide created a 500-meter-high tsunami in a major tourist area

A massive rockslide above Alaska’s Tracy Arm fjord triggered a megatsunami on August 10, 2025.

The wave hit near South Sawyer Glacier and produced a runup of 481 meters on the opposite shore.

Researchers reconstructed the event with satellite data and found glacier thinning and retreat likely helped destabilize the slope.

The early-morning timing meant no injuries, but the case highlights extreme tsunami risks in narrow fjords as climate change reshapes mountain slopes.